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91.
A 43-year-old woman was diagnosed as having stage IV follicular lymphoma. Phenotypically, the lymphoma cells were CD5(-), CD10(+), CD19(+), CD20(+), CD23(-), HLA-DR(+), and IgM-lambda(+). Conventional chromosomal analysis showed a three-way t(3;14;18)(q27;q32;q21) in the lymphoma cells, which was confirmed by spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH). Immunohistochemistry revealed that both BCL2 and BCL6 proteins were expressed in the lymphoma cells, whereas only the BCL6 gene, and not the BCL2 gene, was rearranged by Southern blotting. The patient received combination chemotherapy and has been well for 3 years. This is the first reported case showing a three-way translocation involving 2 major lymphoma-specific abnormalities, 3q27 and t(14;18)(q32;q21).  相似文献   
92.
93.
We analyzed the genetic aberrations on chromosome arms 1p, 10q, and 14q, which are thought to be loci that include putative tumor suppressor genes in meningiomas. We initially conducted molecular genetic testing on a total of 72 tumors including 15 atypical and 8 anaplastic meningiomas using double-target fluorescence in situ hybridization. An incidence of deletion of 1p was observed in 16.3% of histologically benign, 86.7% of atypical, and 87.5% of anaplastic meningiomas. Microsatellite analysis for loss of heterozygosity on 1p, 10q, and 14q was performed in 15 tumors (6 benign, 6 atypical, and 3 anaplastic meningiomas). We detected a limited deleted region on 1p36 in two tumors and suggest a new consistent region of deletion at 1p36.21p23 distal to D1S507 and proximal to D1S214, which spans 8.21 megabases. In addition, loss of 10q was detected in two of three secondary atypical meningiomas, and loss of 14q in two of three primary anaplastic meningiomas. We suggest that one of the putative suppressor genes is located at 1p36.21p23, and that 10q loss may contribute to the malignant progression from benign to atypical meningiomas.  相似文献   
94.
An enzyme-linked immunosorbent assay (ELISA) has been developed for human manganese-superoxide dismutase (Mn-SOD), using a specific monoclonal antibody raised against the purified enzyme. The Mn-SOD molecule comprises four identical sub-units and this permitted the development of a symmetrical assay, using the same monoclonal antibody as both capture and detector. The assay offers a specific, sensitive and convenient means of measuring immunoreactive Mn-SOD in human sera. Under optimum conditions, the sensitivity of the assay permits the detection of 2-200 ng of purified Mn-SOD from human liver. The mean serum Mn-SOD levels of normal healthy males and females were 99.8 +/- 24.8 (mean +/- SD) and 88.8 +/- 20.8 (mean +/- SD), respectively. A high level of the enzyme was found in the sera of patients with acute myocardial infarction as well as malignant diseases such as acute myeloid leukemia, primary hepatoma and gastric cancer. This is the first report of an ELISA using a monoclonal antibody specific for a distinct epitope of Mn-SOD.  相似文献   
95.
An autopsy case of a 19-year-old boy who had shown typical gargoyle features, strictly consistent with mucopolysaccharidosis type II (Hunter's syndrome) was reported. Histologically, cytoplasmic vacuolar change was found In hepatocytes, sinusoidal epithelium of spleen, follicular cells of thyroid, Sertoli cells of testis, chromophobe cell of pituitary and generalized fibroblast-like cells including meninges, cardiac valve and periosteum. The vacuoles consisting of membrane-bound structures with flocculus protein-like material and occasional electron dense bodies on electron microscopy, were considered to be the site of mucopolysaccharide deposition by histochemical analysis. Deposition of lipid material consistent with so-called membranous cytoplasmic body was observed in the neurons of central, peripheral and autonomic nervous system. Hepatosplenomegaly could be explained by cytoplasmic deposition, but the cause of cardiomegaly remained further to be studied. Biochemically hepatic mucopolysaccharide was identified as heparan sulfate, while in the kidney dermatan sulfate and heparan sulfate were detected. The correlation between morphology and biochemistry, and between deposition and degeneration was discussed.  相似文献   
96.
97.
Eighty-one bronchoalveolar lavage (BAL) specimens obtained from 26 HIV-infected, 45 non-HIV immunosuppressed and 10 immunocompetent patients with primary pulmonary diseases were analysed for the presence of Pneumocystis carinii by staining and by P. carinii 5S rDNA determined by PCR. P. carinii was observed by staining of BAL specimens from HIV-infected patients significantly more frequently than those from immunocompromised hosts without HIV infection (57.7% versus 20.0%, respectively). P. carinii 5S rDNA was detected by PCR assay in seven (26.9%) HIV-infected individuals, which was significantly more frequent than for four (8.9%) immunosuppressed patients without HIV infection, for whom staining was negative. None of these patients developed P. carinii pneumonia (PCP) within the follow-up period. BAL specimens from 10 immunocompetent patients with pulmonary disorders were negative for PCP by both staining and PCR assay.  相似文献   
98.
The present study examined the effect of glucocorticoid manipulations on local cerebral blood flow in the hippocampus. We measured local cerebral blood flow in the hippocampus at 1-h intervals over a 1-day period in freely moving rats, by means of the H2 clearance method, before and after sham adrenalectomy, adrenalectomy or adrenalectomy with corticosterone replacement. We also measured local cerebral blood flow in the prefrontal cortex before and after adrenalectomy. Four weeks after the adrenalectomy, hippocampal blood flow at each time of day was an average of 47% greater than before the operation, showing diurnal variation as before. After the sham adrenalectomy or adrenalectomy with corticosterone replacement, hippocampal blood flow did not change significantly with respect to either its level or its diurnal variation. Local cerebral blood flow in the prefrontal cortex increased by only 19% after adrenalectomy. The present study demonstrates that adrenalectomy causes a remarkable increase in hippocampal blood flow, probably due to a lack of corticosterone.  相似文献   
99.
Human visual evoked potentials were recorded during presentation of photos of human and animal faces and various face features. Negative waves with approximate peak latencies of 165 msec (N170) were bilaterally recorded from the occipito-temporal regions. Mean peak latencies of the N170 were shorter for faces than eyes only. Analyses of amplitudes of evoked potentials indicated that the N170 elicited by faces reflected activity of a specific neural system which was insensitive to detailed differences among individual faces regardless of species, and consequently suggest that this system might function to detect existence of faces in general. On the other hand, the mean amplitude of the N170 elicited by human eyes was significantly larger than those by animal eyes. These differences in response latencies and amplitudes of the N170 suggest existence of at least 2 different visual evoked potentials with similar latencies (i.e., N170) which are sensitive to faces in general and human eyes, respectively. Dipole source localization analysis indicated that dipoles for the N170 elicited by eyes were located in the posterior inferior temporal gyrus, and those for faces, located initially in the same region, but moved toward the fusiform and lingual gyri at the late phase of the N170. The results indicated that information processing of faces and eyes separated at least as early as the latency of the N170 at the posterior inferior temporal gyrus as well as the fusiform and lingual gyri, and might provide neurophysiological and anatomical bases to an initial structural encoding stage of human faces.  相似文献   
100.
The effect of 3-nitropropionic acid (3-NP), a selective inhibitor of succinic dehydrogenase, preconditioning on postischemic neurological deterioration and infarction was examined in gerbils after transient ischemia. The animals were pretreated with 1-80mg/kg of 3-NP 1 day before ischemia induced by two 10-min occlusions of the left common carotid artery. Four milligrams per kilogram 3-NP pretreatment significantly ameliorated postischemic neurological deterioration (stroke index at 7 days postischemia, 1.4+/-1.5 vs. 7.4+/-5.4 in 4 mg/kg-pretreated vs. non-pretreated animals: mean+/-SD) and reduced infarct volume (24+/-4.8 vs. 43+/-12 mm(3)). One and 20 mg/kg 3-NP induced milder neuroprotection, and 80 mg/kg 3-NP aggravated postischemic stroke symptoms and infarction. Thus, appropriate doze of 3-NP preconditioning is effective in ameliorating the postischemic neurological deterioration and reducing infarct volume.  相似文献   
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